Electrical controlling system.



A. E. LUNDELL ELECTRICAL CONTROLLING S YSTEM.

APPLICATION FILED NOY. 2|1914.

Patented May-23, 1916.

- //1 ve nib/ A/Je f. L angle/L ALBEN E. LUNDELL, on NEW YORK, N. Y.,ASSIGNOR, BY ivrnsnn ASSIGNMENTS, To wns'rmuv ELECTRIC COMPANY,INCORPORATED, A conromrron or NEW YORK.

ELECTRICAL CONTROLLING SYSTEM;

Specification of Letters Patent.

Patented May 23, 1916.

Application filed November 2, 1914. Serial No. 869,804.

proper performance of telephonic and vari-- ous. signaling andswitch-operating functions by means of controlling circuits extendingover the two wires of each trunk.

In the system herein disclosed to illustrate the preferred embodiment ofthe invention,

'there is provided a supervisory signal and means for controlling itover a signaling circuit extending through one of the two trunk wires,also an automatic ringing mechanism, with means for controlling itsoperation over a second signaling circuit extendingover the other of thetwo trunk wires, for the purpose'of reringing on the called subscribersline. In combination with these there is further provided a switchrestoring magnet with means to operate it under the joint control ofboth of the signaling circuits. The two signaling circuits arepreferably closed during the time the trunk is in use as atelephoniclink between subscriber s stations. Under this condition of theapparatus the supervisory signal located, say at an operators positionat the end of the trunk nearest the calling line, is operated by openingone of the signaling circuits at the switch end of the trunk.The-automatic ringing mechanism which preferably is initially operatedby means local to the switch end of the trunk, can thereafter have itsactive condition reestablished to rering by opening momentarily theother signaling circuit at the operators endof the trunk; and finallythe switch restoring magnet may be operated by simultaneously.

opening both signaling circuits at the operators end of the trunk.

Referring to the drawing, the complete equipment and circuits of atelephone exchange system necessary for the establishment of connectionsselectively between telephone.

parting from the invention. As the system of circuits is shown the bellat the called station has not yet been rung, and'the called subscriberhas not yet lifted his receiving establishing the connection between thesub scribers lines may be manual or automatic, but it is contemplatedthat the switch which 7 101118 the trunk to the called line preferably18 of some automatic type; the iie'storing of whlch, toefiect'disconnection'of the called line from the trunk, may becontrolled from the distant end of the trunk. In the descrip tion thereference character G (not shown in the drawings) is used to designateground connections.

Two subscribers stations 1 and 2 are shown connected by way of contacts3, 4 of a spring-jack and plug-switch 5, contacts 6, 7 of an automaticswitch, two wires 8, 9 of a two-wire interoflice trunk and contacts 10,11' of another automatic switch. The connecting link between thecontacts 3, 4,- and 6, '4' may be divided, as usual, by repeating coilwindings 12, 13 and 14, 15 into inductive sections, and the trunklikewise by repeating coil windings 16, 1'7 and 18, 19.

Current is supplied to the calling line and to the trunk by a battery B20, and toithe called line by a battery B 21. A condenser '22,intermediate the windings 16, 17 makes the calling line section of thetrunk a closed telephonic link;

An automatic ringing mechanism, which may be of any desiredconstruction, com prises, asshown, three relays 23, 24 and 25, a ringinggenerator 26. and a starting switch 27. The closure of tlin startingswitch may be caused, as in automatic systems, to follow immediatelyafter the establishment ofa connection with and test of a Wanted idleline. When thus, or'"in any other manner, this switch is close-d, alocal circuit G (ground), 27, 2s, 29, 23, 30, 31, 32, as, B 21 (battery)is established. This causes ring.- ing relay 23 to act, opening atcontacts 34, 35 the trunk line section leading to the called The variousswitches used for line, and closing the ringing circuit-r26, 24, 36, 82,11, 2, 10, 81, 37, Gringingthe sub.- station bell. When the subscriberresponds, this circuit receives an increase of current, andthe relay 24acts, opening at contact 28 a shunt about relay 25. Relay 25 in turnacts, opening at 29 another contact in this shunt, and closing atcontact 38 a shunt about relay'2'3 which reacts, disconnecting theringing generator from the line and establishing the battery circuit tothe called line. A supervisory relay 39 new acts, closing at contact 40a signaling circuit over wire 9 of the two-wire trunk, as follows: B 20,15, 41, 42, 7, 9, 43, 44, 17, 45, 46, 40, G.

. This circuit includes several contacts, the

v function of which will be stated hereinafter,

an impedance coil which avoids a direct ground connection to thetelephonic link,

and a supervisory relay 41 which acts to shunt a supervisory lamp signal47. Thisif forany reason it is desired to rering the called party, theoperator may reestablish the active condition of the ringing mechanismby momentarily depressing the rering key49. Prior to this, there hadexisted a closed signaling circuit-through the trunk wire 8, as follows:B 21, 50, 51, 52, 53, 16, 8, 6, 54, 55, 14, G; also a second localcircuit: G, 56,57, 31, 32, 33, B 21; and a third local. circuit: G, 58,59, 60, 61, B 21.

The depression of-the rering key, which opens contact 55, causes therelay 53 to react, opening at contact 32 the local ringing and thesecond local circuits. Relay25 opens the shunt about relay 23 andrecloses the shunt about itself. Relay 57 also reacts,

opening at 46 a contact in the supervisory.

signaling circuit, closing at 62 a connection for relay 59 to wire 9v ofthe trunk, and opening at 60 a contact in the third local circuit.Contact 62 makes before contact 60 breaks, so that relay 59 will remainenergized provided it finds a substitute path for battery current overthe trunk wire'9, which it does under the present assumption, the

circuit being as follows: G, 58, 59, 62, 63, 43,

9, 7, 42, 41, 15, B 20. As'the rering key is but moinentarily depressed,the originalfsignaling circuit over the trunk wire 8 be om \closed agar,nd relay 5 acts to 11801088,

the original 'od'ul ringing circuit, causing the ringing relay 23, toagain apply rlnging current to the called line. If and when thesubscriber again responds, relays 24,25 and 23 messes act as before,cutting ofi the ringing current. The operation of reringing may berepeated as often as required.

Assume now that the lines are ready to be discontinued. This, in thesemi-auto-- matic system disclosed, is a condition usually brought aboutby both parties having replaced their receivers, and'both superviof thecalling line This breaks a local cir-' cuit which included a cord relay64 and a cut-o3 relay 65. The former reacts, opening at 66 a-contact inthe calling line super visorysignal circuit, and closing at 67 a circuitfor relay 68, which in turn closes at contact the motor magnet circuitof a sequence switch 69. The function of the sequence switch is tocontrol various circuits in a particular manner, and thus to bring abouta desired sequence of operations. At the time ofthe closure of thelast-mentioned circuit, the sequence switch 69 was resting in talkingposition, say position 16, and it is now moved to the switch returnposition 18, wherein there is closed at contact 70 a circuit for herestoring magnet 71, the function of wh ch is to return to normal theautomatic switch which had previously established the connections atcontacts 6 and 7 between the connecting link and trunk.

Inits movement from position 16 to 18 the sequence switch 69 openedcontacts 72, 73, 74 and 75 in various local circuits, and contacts 54and 42 in the trunk signaling circuits. 'lhereupon relays 53, 25 and 57react as before, and relay 59 is again connected at contact 62 to thetrunk wire 9. In this instance, however, the path for battery current isopen at contact 42 so that relay 59 is not maintained energized, butreacts opening at 51 a contact in the signaling circuit over wire 8, andclosing at contact T. the motor magnet circuit of a sequence switch 77.This sequence switch, like 69, had been resting in talking position, say16, and it is now advanced to the return position 18, wherein at contact78 there is closed the circuit of a nections at contacts 10 and 11between the trunk and the called line. In its movement from position 16to 18, the sequence switch 77 opened contacts 50, 58, 80, 52, 30, 31, 33

and 56 in various local circuits, contacts 43, 44 and 63 in the circuitsof wire 9, and contacts 81 and 82 in the circuit to the called line.Master contacts 83 and 84 are closed between the various restingpositions of the sequence switches. r

g In brief, the operation is as" follows: T

' whereupon ringing relay 23 acts'to connect I over said circuitsjointly.

-line.

the generator 26 to the wanted line. When the called subscriberresponds, relays 24 and 25 act and relay 23 reacts, cutting off theringing current. The called subscriber now has control of thesupervisory signal i? by 7 means of relay 39 in the circuit of his line.This relay reacts when he replaces his receiver, opening the signalingcircuit over wire 9, causing supervisory relay 4:1 to react and thesignal 4;? to be displayed. To rering the operator momentarily depresseskey if), which causes relays 53, 25 and 57 to react, relay 59, however,remaining energized by reason of its connection through contact 62 to,the closed trunk wire 9. Upon the re lease off-key 4L9, thesignaling'circuit over wire 8 isreclosed, and the ringing relay 23 actsas before to connect generator to the To disconnect the signalingcircuits of both trunk Wires 8 and 9 are opened at contacts 54 and 42,followin as in the system disclosed, the removal 0 the plug from thespring-jack of the calling line. Relays 53, 25 and 57 react, as in thecase of reringing, and relay 59 also reacts because it does not find apath for current over the now open trunk-wire 9. The reaction of relay59 causes the energization of the switch-restoring magnet 78. r

' In the particular system described it will be noted that two of thecontrolled devices namely the automatic ringing relay 23 and the switchrestoring magnet ,79 are both dependent for their operation in the firstinstance upon the actuation of switch operating mechanism comprisingtlie'relays 53 and 57, which respond, that is to say, react upon theopening of the trunk circuit over wire 8 and that the operation of theone or the other of these two devices is thereupon selcctivelydetermined by the relay 59,which acts as a testing mechanism todetermine the closed or open condition of the trunk circuit over wire 9.

What is claimed is:

1. In a telephone trunking system, two wires joined to form a telephoniclink and separately forming controlling circuits, a supervis'ory signalunder the control of one and ringing mechanism under the control of theother of said circuits, and a switch controlsaid circuits.

2. In an electricalcontrolling system, two

wires joined to form a telephonic link and separately forming signalingcircuits, sig-' naling devices one at each end of said link controlledoversaid circuits respectively, and a switch controlling devicecontrolled '3.In .a telephone trunking system, two wires joined to forma telephonic link' and separately forming closed controlling circuits, aringing device operable upon the opening of one of said circuits alone,and a switch controlling device operable upon the opening of both saidcircuits.

4.1n a telephone trunking system, two

-wires joined to form a telephonic link and separately vformingindependently operable closed signaling circuits, and a switchcontrolling device operable upon the opening of both said circuits.

6. In an electrical controlling system, two wires extending parallellybetween points and separately forming closed controlling circuits, a,signaling device at one of said points controlled over one of saidcircuits, a signaling dev ce at the other of said points controlled overthe other of said circuits, and

a switch controlling device at one of said points operable under thejoint control of both said circuits 7. In an electrical controllingsystem, two wires extending between two points and separately formingclosed controlling circuits, a signaling device at one of said points,means for operating said device upon the momentary opening of one ofsaid circuits at the other of said points, a second signaling device atsaid other point, means for op erating said-second signaling device uponthe opening of the other of said circuits atthe first mentioned point, aswitch-controlling magnet at the first mentioned point, and means foroperating said magnet-upon the opening of both said circuits at the saidother points.

8. In a telephone-trunking system, two wires extending parallellybetween two points and-separately forming closed controlling circuits, aringing device at one point, means for operating said device upon themomentary opening of one of said circuits. at the other point, asupervisory signal at-said otherpoint, means for operating said signalby opening the other of said circuits at the first mentioned point, aswitchcontrolling magnet at the first mentioned point, and means foroperating said magnet by opening both said circuits at the said otherpoin v 9. In a-telephone exchange system, the combination with atwo-wire trunk, a called subscribers line, a switch connecting saidtrunk and line, a restoringdevice for said switch, and automatic ringingmechanism trolled over one wire of the trunk for reestablishing theactive'condition of the ring- I 7 mg mechanism, and means co'htrolledover both wires of the trunk jointly for operating said restoringdevice.

10. In a telephohe exchange system, the combination with a two-wiretrunk, a called subscibers line, a switch connecting said trunk andline, a restoring device for said switch, ringing mechanism associatedwith the ringing mechanism associated with the switch end of the trunk,and a supervisory signal associated with the other end of the trunk, ofmeans. controlled over the sub scribers line and one wire of thetrunl;for operating the supervisory signal, means controlled over the otherwire of the trunk for operating said ringing mechanism,- and meanscontrolled over both wires of the trunk .for operating said restoringdevice.

trunk and line, a restoring device for said switch, ringing mechanismassociated with the switch end of the trunk, and a SLIPQI'VIS orysignal, of means controlled over the subscribers line and said trunk foroperating the supervisory signal, means controlled over said mechanism,and means also controlled over said trunk for operating said restoringdevice. I

12. Ina telephone exchange system. the

- combination with a'two-wire' trunk, a called subscribers.line, aswitch connecting said trunk and line, automatic ringing mechanismassociated with the switch end of the trunk, and a supervisory signalassociated with the other end of the trunk, of means local to the switchend of the trunk for rendering said ringing mechanism active, meanscontrolled over the subscribers line for rendering the ringing'mechanism inactive, means controlled over said trunk for reestablishingthe active condition of the ringing mechanism, and means controlled overthe subscribers line and said trunk for operating the said supervisorysignal.

13. In a telephone exchange system, two Wires joining to form atelephonic trunk and each forming an 1 independentcontrolling circuit, asignaling device at one' end of said trunk, a second signaling deviceand a switch-controllingmagnet at the other end of said trunk, a switchat the last mentioned end of the trunk adapted to open one of thecontrolling circuits to operate the first mentioned signaling device,

a switch at the first mentioned end of the vice, a switch at the saidfirst mentioned end masses of the trunk adapted to open the first men-.tioned controlling circuit, and means con ing between said points andeach forming a closed controlling circuit, means for operating one ofthe first mentioned devices by momentarily opening one of saidcontrolling circuits, means'ior operating the said third device byopening the other of said controlling circuits, and means for operatingthe other of the said first mentioned devices by opening both saidcontrolling circuits.

15. A controlling system comprising two devices at one point to becontrolled from a distant point, two closed circuits extending betweensaid points, means at the dis-'- tant point for opening one or both ofsaid circuits atwill, switch operating mechanism at the first mentionedpoint responsive to the opening of one of said circuits, a testingmechanism adapted upon the actuation of said switch operating mechanismwhen said circuit is opened to test the condition of the other circuit,the operation of the two devices both being dependent upon the actuationof said switch operating mechanism but selectively determined by saidtesting mechillllfilll.

16. In a telephone exchange, the combination with a system of circuitsbetween lines includinga two-wire trunk, and an automatic ringingapparatus and a switch restoring device at the incoming end and asupervisory signaling device at the outgoing end of said trunk. of meanscontrolled over said trunk for resorting the automatic ringingapparatus. means. .controlled over said trunk for operating said switchrestoring device, and means controlled over said trunk "for operatingsaid supervisory signaling device, the control of said automatic ringingapparatus and said supervisory signaling device being effected withoutinterfcrence with the control of said switch restoring device.

In witness whereof, I hereunto subscribe my name this 29th day ofOctober, A. D.

. ALBEN E. LUNDELL. Witnesses E. Emma, K. L. STAHL.

